Les Bleus, who were knocked out in the first round in South Africa following off-pitch dramas, qualified for the European finals although they failed to impress over the qualifying campaign despite winning their group by a point from Bosnia and losing only once in their 10 games.
Blanc, who took over from Raymond Domenech after the World Cup debacle told the sports daily L'Equipe on Friday that people should not expect miracles from France in Poland and Ukraine next summer.
"In 15 months, people want us to have a great team with great players and play like the Netherlands, Spain or Germany. It is impossible!," Blanc said.
"We said, and we say it again, that it would take time. You don't buy quality of play, or a team, in the supermarket."
Blanc added that writing off those involved in the South Africa farce had never been an option.
The France players went on strike after striker Nicolas Anelka was kicked out of the squad for insulting Domenech at half-time in a first-round game against Mexico.
"The scar will always be there. We have to live with it. They all did a stupid thing. All of them," said Blanc.
"We could have said: 'people don't want to see them. All those who were there in South Africa, it's over! They're 22, 23? We don't care! Then people would have been happy.
"The only problem is that after three games and three defeats, the same people would have been screaming 'we want a France team that wins, that's all.
"So either we did that, or we did what we just did: keeping these players but trying to change their state of mind. Four or five years were needed for the first solution and I was not up for it."
France, who are 12th in the FIFA world rankings, could be in Pot 4 of the lowest ranked teams when the draw for the finals is made in Kiev on December 2 - and that's a cause for concern for Blanc.
"If we have Spain and Germany in our group, it will be very tough to get through the first round," said Blanc.
"People can fantasise but I am telling you the truth."
No matter what happens in Poland and Ukraine or in the subsequent World Cup qualifying campaign for the 2014 finals in Brazil at least France are assured of a place in the 2016 Euro finals as the host nation of what will be the first expanded 24-team tournament.
